This southern sea otter is settling down to rest in a small patch of Egregia feather boa kelp. Image: Lilian Carswell/USFWS

When sea otters want to rest, they wrap a piece of kelp around their body to hold themselves steady among the rolling waves. Likewise, California’s sea otter numbers are holding steady against the many forces pushing against their population recovery, according to the latest field survey led by federal, state, aquarium, and university scientists.

For 2014, USGS reports the population index as 2,944 (data available online). It’s a negligible bump from the 2013 report of 2,939.

For southern sea otters to be considered for removal from the “Threatened” species list, the population index would have to exceed 3,090 for three consecutive years, according to the Southern Sea Otter Recovery Plan established by the U.S. Fish and Wildlife Service.

Trends in population index reported by USGS for southern sea otters in California. Data are shown for independent otters (non‐pups) and all otters for mainland California (blue; left axis), San Nicolas Island (red; right axis), and range-wide (squares; left axis) from 2012 onward, when both indices were combined to calculate the population index. Image: USGS

“For an animal so few in number, sea otter population trends can be influenced by many local and range-wide factors,” says biologist Tim Tinker with the USGS Western Ecological Research Center, who leads California sea otter research with co-investigators from the California Department of Fish and Wildlife’s Office of Spill Prevention and Response, the Monterey Bay Aquarium, University of California, Santa Cruz, and other institutions. “We are seeing elevated mortality suggestive of food resource limitation in some parts of the range, and increasing mortality from white shark attacks in others. But our federal, state, aquarium, and university sea otter research alliance is making progress in understanding how all these trends relate to environmental factors along the California coast.”

California sea otters feed and live in the “nearshore marine ecosystem” — the stretch of ocean that hugs a shoreline—making them a good indicator species for detecting pollutants and pathogens washed down from coastlands. And along many parts of Pacific North America, sea otters play critical roles in natural food webs, keeping important ecosystems like kelp forests and seagrass beds in balance.

Studying sea otters, then, not only helps us understand their population recovery, but it also uncovers clues on the health and rhythm of nearshore marine ecosystems — the same waters many people swim, fish, and make a living in every day.

Sea otters live at the edge of the land and sea environments, like these idyllic sun-lit waters in Big Sur, California — the same nearshore ocean waters that humans use and enjoy. Image: Ben Young Landis/USGS

Mothers and Pups

Sea otters were presumed extinct in California after the 19th Century fur trade years but were rediscovered in the 1930s by the public, when as few as 50 animals were documented persisting in nearshore areas off the coast of Big Sur.

In that context, the present state of sea otters in California isn’t terrible. But population recovery has been slow. Part of the reason is the extreme, edge-of-the-knife life history of sea otters.

Not equipped with blubber like whales and seals, sea otters must rely on their fur coat and their super-high metabolic rate to stay warm. “The average adult sea otter has to actively hunt and eat 20 to 30 percent of its body mass in food each day just to meet its energy requirements,” says Tinker.

Indeed, researchers have documented a high mortality rate in prime-breeding-age female sea otters in California from what they call “end-lactation syndrome” — where females are so underweight and energetically stressed after raising a pup that they are more vulnerable to life-threatening diseases and infections.

The new research offers an explanation for the high mortality in breeding-age females in the center part of the sea otter’s California range (Seaside to Cayucos) — which is likely at or near “carrying capacity,” the maximum population size that can be sustained over the long term by the resources available in the area.

Map of central California showing variation in local population densities of southern sea otters along the mainland coast and San Nicolas Island. Image: USGS

“These fundamentally high energy demands are likely the underlying reason why we see so much mortality among prime-age females in the middle of their geographic range, where the density of the sea otter population is highest and resources are limited,” explains study lead author Nicole Thometz of UC Santa Cruz. “In the center of the range, they appear to be up against their physiological limits.”

But give even more credit to these sea otter moms: the 2014 population index also reported a record high for pups.

“The ratio of dependent pups to adult otters remains high overall, and together with data from tagging studies, that tells us that reproductive rates are within the normal range and not limiting recovery,” says USGS biologist Brian Hatfield, who coordinates the annual population survey.

A southern sea otter mother and pup at the Monterey Bay Aquarium, which collaborates on sea otter research with USGS and other institutions. Video: Monterey Bay Aquarium

Le Morte d’Otter

Of course, it remains to be seen whether more pups will translate into overall population growth.

The State of California studies dead sea otters, like this one found by USGS scientists in Piedras Blancas, Calif., to learn about their causes of death and to understand the variety of environment stress factors that impact the nearshore marine environment. Image: Brian Hatfield/USGS

These necropsies are how scientists learned about the increase in bite wounds from great white sharks — apparently the result of “exploratory bites” that do not lead to consumption of the otter by the shark, but that nonetheless often result in the death of the otter. This cause of death has been common at the north end of the range (from Pigeon Point to Seaside) for some time, but in recent years it has become most intense in the southern end of the range (from Cayucos to Gaviota) — to the point where the adult population now has a declining trend.

Not great news for the dense patch of sea otters stuck in the central range, trying to expand northward and southward.

In addition to end-lactation syndrome and shark bites, the state’s “CSI: Sea Otter” laboratory has revealed many other causes of death for sea otters across California. Over the years, California state veterinarians have found sea otters poisoned by the microbial toxin microcystin — which can flow into the sea after blooming in warm lakes with an overabundance of nutrients — as well as sea otters infected with protozoan parasites that can cause fatal brain infections, including Toxoplasma gondii, which is transmitted in the feces of wild and domestic cats.

That’s a lot of different factors determining the survival of a creature central to the survival of giant kelp forests — the underwater jungles teeming with marine life that stretch from California to Alaska.

“Sea otters are considered a keystone species of the kelp ecosystem because they are such voracious predators, and they are uniquely capable of limiting herbivorous invertebrates like sea urchins that, if left unchecked, can decimate kelp beds and the fish habitat they provide,” says USGS biologist Tim Tinker, who with his mentor Jim Estes coauthored a 1998 study that described this epic circle of life in Alaskan waters.

The alliance of USGS, U.S. Fish and Wildlife Service, state, aquarium, and university researchers are continuing to study the ecological and environmental roles that sea otters can play, not only in kelp forests of the outer coast, but in protected tidal estuaries as well.

The Elkhorn Slough National Estuarine Research Reserve, Elkhorn Slough Foundation and Friends of the Sea Otter operate a webcam that allows the public to view sea otters in the tidal wetlands of the Elkhorn Slough, near Monterey, California, where USGS and other researchers are studying this Threatened species. Click this link to view the live webcam.

As for the sea otter numbers in California, USGS and alliance researchers are currently analyzing more than a decade of research to tease out the driving factors tempering their population recovery and spread — a recovery, as new findings continue to show, that should benefit California’s nearshore marine ecosystem.

“We already knew that sea otters played a vital role in coastal ecosystems, but the exciting discoveries of the last several years suggest that we have really only begun to understand the far-reaching effects of this top predator,” says Lilian Carswell, Southern Sea Otter Recovery Coordinator for the U.S. Fish and Wildlife Service. “If sea otters can recolonize new areas of their historic range, we are almost certain to see an upswing in population growth. That will be good for sea otter recovery, good for the nearshore environment, good for all of us—because we all benefit from the services that intact ecosystems provide.”

Sea Otter Awareness Week is held every year in September to put a spotlight on the world of sea otters, and to highlight ongoing conservation efforts to ensure these beautiful creatures remain a part of our marine environment. Photo courtesy of Ron Eby.

The annual population index is calculated using visual surveys conducted along the California coastline by researchers, students and volunteers from USGS, California Department of Fish and Wildlife’s Office of Spill Prevention and Response, Monterey Bay Aquarium, University of California-Santa Cruz, U.S. Fish and Wildlife Service, U.S. Bureau of Ocean Energy Management, and the Santa Barbara Zoo.

Visual survey data from multiple years are averaged to calculate the annual population index, in order to compensate for year-to-year variability in observation conditions, and to give scientists a more reliable picture of sea otter abundance trends.

In 2013, the equation for the population index was amended to add sea otters living at San Nicolas Island, in the Channel Islands offshore of Los Angeles. Sea otters were introduced to the island in the 1980s as part of a U.S. Fish and Wildlife Service recovery experiment, but most returned to the mainland or disappeared, and some are known to have died. The Service reassessed and ended the experimental program in December 2012, and the remaining sea otters at San Nicolas Island are now counted as part of the California-wide population index.

Appreciating Sea Otters, Safely

Sea otters can be found in nearshore areas along the California coastline, including areas of high human activity, such as harbors. Like any other wild animals—especially carnivores—they should be appreciated from a distance. Here are some tips for watching sea otters, suggested by the Monterey Bay Aquarium and the U.S. Fish and Wildlife Service.

Take caution in areas where sea otters are known to be present.

Keep a safe distance from sea otters and other wildlife. If the otter notices you, you are likely too close and should back away.

Keep pets on a leash on and around docks and harbors.

Never feed sea otters or other wildlife. Wild animals that are fed can become aggressive.

#OtterWeek Resources

From September 21-27, 2014, research and education institutions in California and around the U.S. are hosting sea otter science events as part of the annual Sea Otter Awareness Week.

Look for public lectures featuring scientists from USGS and other organizations in this year’s schedule, and use the hashtag #SeaOtterWeek when you share otter science facts online!

For Reporters

Data and figures from the annual survey are available on the USGS project website. Sea otter biologists from California research institutions are available for media requests during #SeaOtterWeek. Please contact the following media offices:

USGS provides science for a changing world — including its oceans. Image: Ben Young Landis/USGS

]]>http://www.usgs.gov/blogs/features/usgs_top_story/slowly-swimming-towards-recovery-californias-sea-otter-numbers-holding-steady/feed/0This southern sea otter is settling down to rest in a small patch of Egregia feather boa kelp. Image: Lilian Carswell/USFWS2014 Spring Survey Figure2xTrends in population index reported by USGS for southern sea otters in California. Data are shown for independent otters (non‐pups) and all otters for mainland California (blue; left axis), San Nicolas Island (red; right axis), and range-wide (squares; left axis) from 2012 onward, when both indices were combined to calculate the population index. Image: USGS (Download PDF)Sea otters live at the edge of the land and sea environments, like these idyllic sun-lit waters in Big Sur, California — the same nearshore ocean waters that humans use and enjoy. Image: Ben Young Landis/USGS2014 Spring Survey Figure5xMap of central California showing variation in local population densities of southern sea otters along the mainland coast and San Nicolas Island. Image: USGS (Download PDF)The State of California studies dead sea otters, like this one found by USGS scientists in Piedras Blancas, Calif., to learn about their causes of death and to understand the variety of environment stress factors that impact the nearshore marine environment. Image: Brian Hatfield/USGS15259513562_ba4bb1b056_bSea Otter Awareness Week is held every year in September to put a spotlight on the world of sea otters, and to highlight ongoing conservation efforts to ensure these beautiful creatures remain a part of our marine environment. Photo courtesy of Ron Eby.USGS provides science for a changing world — including its oceans. Image: Ben Young Landis/USGSBattling Botulism in Birdshttp://www.usgs.gov/blogs/features/usgs_top_story/battling-botulism-in-birds/
http://www.usgs.gov/blogs/features/usgs_top_story/battling-botulism-in-birds/#commentsThu, 13 Feb 2014 18:03:54 +0000anewmanhttp://www.usgs.gov/blogs/features/?post_type=usgs_top_story&p=191311Read more]]>

A paralyzing disease known as botulism has killed over 100,000 birds in parts of the Great Lakes since 1999. The outbreak is particularly harmful to some species of water birds, silencing the haunting call of many common loons and further threatening the federally endangered piping plover.

Scientific mysteries and partially answered questions surround the botulism outbreaks: How does the toxin spread through the food chain? What causes and sustains outbreaks in the Great Lakes? How can it be controlled or eliminated? The U.S. Geological Survey, in collaboration with the National Park Service, U.S. Fish and Wildlife Service and other partners, and funded through the Great Lakes Restoration Initiative, is studying avian botulism to better understand and help mitigate deadly outbreaks in the Great Lakes.

“Botulism, we believe, is a consequence of Great Lakes ecosystems distressed by invasive species and disturbed delicate food webs,” said Jonathan Sleeman, Director of the USGS National Wildlife Health Center (NWHC). “We are working to detect botulinum toxin in the environment and determine how the toxin reaches and affects birds.”

Avian botulism is a deadly food poisoning of wildlife, caused by a toxin produced by the naturally occurring soil bacterium, Clostridium botulinum. The toxin likely accumulates in some invertebrate and fish species, which are then eaten by vulnerable water birds.

Two types of botulism are deadly to birds such as waterfowl, shorebirds, and colonial water birds. The majority of avian botulism is caused by Type C toxin, which can occur annually on wetlands, lakes, and ponds, while Type E toxin is limited primarily to the Great Lakes (but also occurs in Europe and other locations outside of the U.S.).

Botulism in humans is usually the result of eating improperly home-canned foods, which contain types A or B toxin. Type E intoxication of humans has been associated with improperly smoked fish. Thorough cooking destroys botulinum toxin that may be present in food.

An extensive problem

Outbreaks of avian botulism Type E have resulted in periodic and often severe die-offs of fish-eating birds in the Great Lakes since at least the 1960s, but have become common since 1999, particularly in Lakes Michigan and Erie.For example, in 2012, over 4,000 botulism-afflicted birds were found dead on Lake Michigan beaches.

On a larger scale, the USGS NWHC in Madison, Wisc., has developed an interactive national map showing the number of bird deaths primarily related to botulism Type C, when each outbreak occurred, and the top species affected, based on 25 years of bird mortality data.

At the base of the food web

Spores of the botulism bacterium are widely distributed throughout the environment, but can become active and produce toxins under suitable environmental conditions, such as warm temperatures coupled with the presence of decomposing plants and invertebrates. In some cases, birds may ingest the toxin by consuming decaying organic matter directly, or by eating live invertebrates whose food was laden with the toxin.

USGS and National Park Service scientists are studying potential connections between toxin production, lake-bottom sediment and water conditions, and the presence of invasive species such as zebra mussels, quagga mussels, and round gobies. The mussels create a hard surface on the lake bottom which allows algae to attach in places where it could not previously, and the mussels filter lake water and make it clearer. The clear water allows sunlight to reach further down into the lake and, combined with the increase in phosphorus from mussel excretion, human industry and agriculture along the shoreline, promotes extensive growth of the nuisance alga Cladophora. Later in the summer, the alga dies and decays on the lake bottom, creating a low-oxygen environment favorable to the botulism bacterium.

Together, these impairments can lead to death by drowning, respiratory failure, or vulnerability to predators.

Battling back

The USGS and its partners are studying avian botulism on both microscopic and geographic scales as part of the Great Lakes Restoration Initiative. Information gleaned from this research will help resource managers develop strategies to prevent or reduce the impacts of devastating botulism outbreaks in the Great Lakes.

Under the microscope

USGS researchers and their partners are investigating where and how Clostridium botulinum grows in Lake Michigan to uncover factors that cause botulism in water birds.

“Determining precisely where botulism outbreaks occur will allow us to further determine how birds ingest the toxin,” said USGS microbiologist David Blehert. “To facilitate this research, we are working to improve our capacity to detect the botulinum toxin.”

Laboratory tests following necropsies, or wildlife autopsies, are used to determine whether botulinum toxin was a cause of death in birds, and these analyses are conducted at the USGS NWHC. Work is underway to develop novel biochemical tests to more precisely determine the amounts of botulinum toxin in tissues from birds, fish or invertebrates. Molecular tests are also used to determine the amounts of toxin-producing bacteria in environmental samples, such as sand, mud, or water.

From the sky

The USGS Upper Midwest Environmental Sciences Center (UMESC) in La Crosse, Wisc., is studying the distribution, movement, and feeding patterns of water birds to help determine where and how they come into contact with the botulinum toxin. This information will eventually help identify what drives botulism outbreaks in the Great Lakes for wildlife management purposes.

“Our research can help managers effectively focus their conservation efforts,” said USGS scientist Kevin Kenow. “If we know where loons and other waterbirds obtain contaminated food, management tactics can be targeted to those areas.”

Kenow and his colleagues use aerial surveys and tracking technology to determine migration and feeding patterns of the iconic common loon. Satellite

The USGS is using electronic geolocator tags and satellite transmitters to record loon activity and help determine how and where water birds are exposed to botulism in the Great Lakes.

tracking devices implanted in loons from Minnesota, Wisconsin, and the Michigan Upper Peninsula help scientists determine where the birds are spending time on the Great Lakes during their seasonal migrations, and where additional research could focus to provide insight on routes of exposure to the botulinum toxin.

Other loons are tagged with electronic geolocators, which record daily information about the birds’ specific feeding behavior. Geolocator data, such as location, temperature, light levels, and pressure, tell how far down in the water loons dive for fish: Close to 150-foot dives have been recorded, suggesting that loons may be exposed to the toxin in deep offshore waters.

A USGS volunteer looks for birds while monitoring his assigned beach on Lake Michigan as part of the AMBLE citizen science program.

A beach strewn with lifeless birds is a disheartening sight. However, some citizens have been channeling their concern into action through the Avian Monitoring for Botulism Lakeshore Events (AMBLE) citizen science program. Established by the USGS in 2011, AMBLE trained volunteers to monitor, count, and collect data on bird carcasses found along the shores of northern Lake Michigan. The 2011 AMBLE focus area was Door County, Wisc., and was expanded to include some of the Green Bay shoreline in 2012.

Data collected are entered into an online portal maintained by the USGS NWHC, and especially when combined with data collected by NPS volunteers and biologists around northern Lake Michigan, provide valuable information about the timing, severity, and bird species affected by botulism.

“We are using data collected by beach monitors to create a statistical model, or representation, of the pulses of reported mortality in space and time,” said USGS scientist Jenny Chipault. “Repeat data from 2013 will validate and strengthen the model and ultimately help define Lake Michigan bird mortality trends.”

Data on bird mortality are also being used to help determine the locations of intoxication based on the ecological characteristics of the species involved.

AMBLE volunteers are specifically trained in safe handling and disposal of wildlife carcasses they may find.

“In general, untrained people should not pick up or touch sick or dead wildlife,” said Stephen Riley, USGS scientist and lead of the Great Lakes botulism study. “Instead, they should alert their state wildlife officials about the location, and those officials will properly dispose of the carcasses.”

More information

For more information on USGS avian botulism and wildlife disease research, please visit the following websites:

Despite decades of scientific work on the Florida panther, accurate population estimates have been difficult to come by due to the big cat’s low numbers, elusiveness and secretive nature. Nevertheless, USGS scientists in collaboration with North Carolina State University researchers have developed a method to accurately estimate population size and density for this mysterious felid, the last remaining puma subspecies in eastern North America and one of the most endangered felids world-wide. Other endangered felids include: jaguars, tigers, leopards, etc.

Drs. J. Andrew Royle, Richard Chandler, and Allan F. O’Connell of the USGS Patuxent Wildlife Research Center were the principal investigators on a research team that used camera trap data to develop a revolutionary spatial capture-recapture model that not only generates statistically reliable density estimates, but does so even when individual animals are not identifiable, as was the case for the Florida panther. This work is easily applicable to other species that lack distinguishing marks and can be replicated for studying other threatened or endangered species, especially large carnivores that exist at low densities and are difficult to sample. In addition, these models can be applied to a variety of non-invasive sampling techniques, such as remote photography that limit the risk of death or injury to both animal and handlers. The spatial capture-recapture model requires that only a small number of individuals within the local panther population be “marked” or “collared” (i.e., identified).

In this particular study, the capture-recapture model was used to assist Florida’s wildlife managers to collect an estimate of population size and density for a portion of the panther’s range in southwest Florida, where the Army Corps of Engineers is rehabilitating the natural habitat that is immediately adjacent to the Florida Panther National Wildlife Refuge, one of the last remaining strongholds of this endangered felid.

Brief Background of the Florida Panther

The Florida panther is a member of the cat family (felidae) and is recognized as a subspecies of puma. Males can reach up to seven feet in length and 160 pounds, whereas the females are generally smaller: 6 feet and 110 pounds. Their large size can be attributed to their predatory diets consisting of white-tailed deer, as well as feral hogs, rabbits, raccoons, armadillos, birds, and occasionally alligators. Though not as big as the males, female panthers often live up to twice as long in the wild (10-12 years). Male panthers have a tendency to kill one another in the wild because their current habitats are smaller than their home range of 200 square miles, whereas females tend to have smaller ranges of 75 square miles. The leading cause of death for the panther is road kill. Given the declining population of males and the 92-96-day gestation period (pregnancy), reproducing only 1-4 kittens per litter is not enough offspring to sustain the declining population, especially with the high kitten mortality rate.

Florida panther; Puma concolor coryi, remains one of the most endangered mammals in the world.

The Florida panther has been considered endangered since 1967, and qualifies for protection under the federal Endangered Species Act of 1973. Since its listing, the species has remained endangered, and in the early 1990s the population reached a low between 20-30 individuals. Before this new tracking model, it was difficult to determine the appropriate conservation efforts needed to save the species because the population number was unknown.

Not only is the Florida panther the inspiration behind one of the state’s two National Hockey League franchises, but along with their other cat brethren, have been inhabitants and walking the planet for nearly 30 million years.

Concluding Thought

Advances in non-invasive sampling techniques, along with enhanced modeling, can improve the understanding of animal populations and how they exist in the natural world. Accurate population numbers as well as ensuring safe research practices can help preserve the existence of the Florida panther and other endangered species throughout the world.

]]>http://www.usgs.gov/blogs/features/usgs_top_story/capturing-and-recapturing-the-moment-preserving-the-florida-panther/feed/0A family of Florida panthers walking in the night.Florida panther; Puma concolor coryi, remains one of the most endangered mammals in the world. How to Live with Wildfires in Southern Californiahttp://www.usgs.gov/blogs/features/usgs_top_story/how-to-live-with-wildfires-in-southern-california/
http://www.usgs.gov/blogs/features/usgs_top_story/how-to-live-with-wildfires-in-southern-california/#commentsMon, 26 Aug 2013 16:10:16 +0000Aqsa Ahmedhttp://www.usgs.gov/blogs/features/?post_type=usgs_top_story&p=182472Read more]]>

A wall of fire in southern California. Image courtesy of Tim Walton, Photo One Productions, CALFIRE. Shared with permission.

Los Angeles. San Diego. Santa Barbara. These are some of the most recognizable locales in the United States, if not the world. The mere mention of these names evokes visions of sun-soaked beaches, warm breezes, glamorous homes, legendary traffic and the vibrant, pulsing buzz of humanity and culture.

Yet as locals know, these regions of unparalleled fame and economic importance are also united by another feature: devastating wildfires.

Southern California’s fire ecology is unlike that of anywhere else in the United States. Fire control strategies developed for mountain forests don’t have the same results here. Year after year, wildfires continue to incur tremendous economic and emotional costs to homeowners and communities.

“We have averaged something like 500 homes per year lost since the 1950’s,” says U.S. Geological Survey and UCLA fire ecologist Jon Keeley. “Now despite very effective fire suppression efforts, the situation seems to have only gotten worse, so that since the year 2000 we’ve averaged a loss of a thousand homes per year from wildfires.”

Why are southern California’s fire losses worsening? What factors drive southern California’s fire risk and fire ecology? Are there solutions that can help southern California communities manage their fire risks, while sustaining native habitats and species?

“The weather conditions that cause these fires occur every year, thus in southern California we need to change the way we look at fires,” says Keeley, who co-leads the project with Alexandra Syphard of the Conservation Biology Institute, Ross Bradstock of the University of Wollongong in Australia, and other colleagues.

On the wildland side, USGS scientists also are trying to understand the nuanced role of wildfires in southern California’s native chaparral ecosystem. “In our research, we saw that many small wildlife species had trouble recovering from landscape-scale fires for at least ten years post-fire,” says USGS ecologist Robert Fisher, another project leader. “That pattern hints at how catastrophic fires also have lasting impacts on our biological communities.”

USGS Western Ecological Research Center ecologist Carlton Rochester studies the effects of fire on wildlife in San Diego County, Calif. Image Credit: USGS.

The project has attracted the cooperation and attention of southern California natural resource managers, including the Santa Monica Mountains National Recreation Area — the largest urban national park in the U.S. and home to residential communities such as Thousand Oaks.

“So, it’s time to re-examine how we look at these problems to find out what is effective, so that dollars we put into wildfire losses actually has a benefit that we actually see a reduction in those losses in the future,” says National Park Service fire ecologist Marti Witter in the film. “The really important part about having rigorous scientific data to back up the recommendations that we make is because they are counter-

intuitive, because they run contrary to the way work has been done for thirty years.”

The project scientists continue to study the many factors that dictate wildfire impacts to southern California. Ultimately, they hope to integrate all of these wildfire factors into a decision model that can be used by local fire managers and land use planners. The model will give communities a tool to understand which combination of strategies — from fuel treatments, to land use planning, to urban landscaping — will have the greatest potential for managing wildfire risk in southern California.

Wildfires are an inevitable feature of southern California, but the risks wildfires pose to communities and landscapes can be managed. USGS hopes to contribute its strengths in natural hazards science and landscape ecology to provide communities with new scientific data and new strategies — knowledge that may someday show us how to live with fire in southern California.

]]>http://www.usgs.gov/blogs/features/usgs_top_story/how-to-live-with-wildfires-in-southern-california/feed/0A Wall of Fire in Southern California USGS Scientists Discuss Southern California Fire EcologyUSGS Ecologist Carlton Rochester Handling a Rattlesnake Southern California's Fire LandscapeSan Francisco Bay Could Lose Marshes to Sea-Level Rise by 2100.http://www.usgs.gov/blogs/features/usgs_top_story/san-francisco-bay-could-lose-marshes-to-sea-level-rise-by-2100-2/
http://www.usgs.gov/blogs/features/usgs_top_story/san-francisco-bay-could-lose-marshes-to-sea-level-rise-by-2100-2/#commentsTue, 28 May 2013 11:30:37 +0000Aqsa Ahmedhttp://www.usgs.gov/blogs/features/?post_type=usgs_top_story&p=178562Read more]]>San Francisco Bay — which has already lost the majority of its marsh habitat since the 19th Century — could lose even more marshes by the year 2100, due to sea level rise.

Using a new computer model, they found that 95 percent (4,798 acres) of these 12 marshes will be inundated by 2100 under a four-foot sea-level rise scenario — losing their vegetation and being converted into tidal mudflat habitats.

“Future inhabitants of the Bay Area shoreline will see a very different set of wetlands and wildlife, according to our model,” says USGS ecologist and study author Karen Thorne. “Losing marshes means losing the wild birds and animal species that depend on them, and we also lose the natural infrastructure that marshes serve as — as buffers against extreme tides and floods.”

The study sites represent about 12 percent of the remaining marshes in San Francisco Bay overall. Results of the study are published in USGS Open-File Report 2013-1081, and videos of the sea level rise scenarios for the study sites can be viewed at the project website: www.werc.usgs.gov/SFBaySLR.

Researchers painstakingly surveyed the marshes using sophisticated “RTK GPS” instruments (see Tech Tidbit, below) — which are capable of measuring elevation within a two-centimeter (0.78 inch) resolution. With this ability, researchers not only mapped the marsh topography, but they mapped the layout of the marsh plants as well — a previously unavailable, yet crucial dataset.

Animations, graphs and data from the San Francisco Bay sea level rise study.

Alternate Futures?

The report has implications for habitat restoration efforts for San Francisco Bay’s national wildlife refuges. And the implications of the study are not necessarily bleak.

“San Francisco Bay is home to one of the world’s most vibrant centers of society and commerce, but it also means that our remaining marshes are often fenced in by urban barriers, and there’s little high ground left for marsh plants to naturally spread and adapt to rising seas,” says Don Brubaker, manager of the San Pablo Bay National Wildlife Refuge. “But if there are other things we can do to help our existing marshes become more resilient to future changes and give migratory birds and endangered wildlife more habitat and time to adapt to sea level rise effects, then we might be able to keep pace with sea-level rise.”

“This new report actually underscores the need to restore more marshes to San Francisco Bay,” says Eric Mruz, refuge manager at the Don Edwards San Francisco Bay National Wildlife Refuge, also one of the sites of the South Bay Salt Pond Restoration Project. “The study is based on current conditions. But if we change that equation, and have more acres of marshes and healthier marshes on hand to begin with, then maybe we’ll have a different outcome 100 years from now.”

The salt marsh harvest mouse (Reithrodontomys raviventris) is an endangered species dependent on San Francisco Bay marshes. Image Credit: USGS

Local cooperators in San Francisco Bay include USFWS, NOAA, National Estuarine Research Reserve System, California Department of Fish and Wildlife, California State Parks, East Bay Regional Parks, City of Oakland and San Francisco International Airport.

Tech Tidbit: What is an RTK GPS?

RTK GPS stands for “real-time kinematic global positioning system”. However, unlike GPS units commonly used by consumers, RTK GPS systems require a “base unit” in addition to the measuring unit (the tall pole device held by the USGS technician in the photo). In urban areas like San Francisco Bay, local cell phone tower networks can sometimes function as the base unit.

The system then measures the relative difference in positions between the base unit and the measuring unit.

RTK GPS offers very high resolution within 2 cm for elevation measurement — the span of a U.S. nickel coin and easily the difference in height between low-growing and taller-growing plant species. And the horizontal x- and y-axis positions can be closer to 1 cm or less in resolution.

There are other technical differences, but in essence RTK GPS systems have excellent applications for land surveys, especially where a high-precision instrument is needed to discern elevation changes in areas with very little slope — much like the marsh vegetation and elevation surveys required of this USGS project.

The endangered West Indian manatee is a large, plant-eating, slow moving mammal found in the southeastern United States, Caribbean Islands, eastern Mexico and Central America, and the northern coast and rivers of South America.

Florida’s state marine mammal gets a check-up each year by a team of biologists, veterinarians and experienced volunteers who conduct health assessments of the manatees captured at Crystal River National Wildlife Refuge in the late fall and winter.

Crystal River is one of several sites where USGS has successfully captured, examined and released more than 400 manatees over the past 10 years. The researchers choose sites that manatees frequent during the cold winter months – typically areas near springs or other sources of warmer water where large numbers of manatees congregate — making it easier for biologists to assess many animals in a short period of time.

Why examine manatees?

Health assessments are a valuable tool to determine the fitness, specifically related to environmental and medical issues, of any population of wildlife. Biologists also use information from the assessments to understand the basics of manatee health in order to ensure that rescued and captive animals are properly cared for. Marine mammals, such as manatees, are often used as sentinels for emerging threats to the ocean environment and human health.

Manatees are an endangered species, so all clinical procedures are con­ducted by experienced biologists and veterinary personnel. A special wildlife research permit is required. Since manatees, unlike people, do not voluntarily get physicals, a large team works together to capture and examine the manatees. In the water, manatees selected for capture are circled with a large net and pulled onto the beach by an experienced capture team.

The Physical Exam

Once on shore, the manatees will receive a complete medi­cal examination by veterinarians on the assessment team. Blood is drawn under sterile conditions from a flipper, centrifuged for plasma and serum separation, and submitted for routine blood analyses to assess health condition and establish baseline normal values for the manatee population.

Female manatee nursing calf

A manatee physical exam includes the following:

• General Appearance

• Body Condition

• Photo-documentation of any lesions and wounds

• Heart/Pulse Rate

• Respiratory Rate

• Temperature

• Body weight

• Complete body measurements (body length and girths)

• Eye exam

• Implantation of PIT tag (used to identify individual manatees, just like microchips in pets)

Manatees are entirely aquatic, and as herbivores eat a wide variety of aquatic plants, including seagrass, water hyacinths and shoreline vegetation.

Ranging in color from gray to brown, the average adult manatee is about 10 feet long and weighs between 1,500 and 2,200 pounds. Newborn manatees range in size from four to four and a half feet long and weigh about 60 pounds. Manatee life expectancy is about 60 years.

Manatees cannot survive for extended periods in water colder than about 63°F, and prefer temperatures warmer than 72°F.

Manatees live in shallow fresh, brackish and marine aquatic habitats, traveling readily among them. In Florida, they travel considerable distances during the winter to access warm water habitat, such as artesian springs and the heated discharges of power generating plants. Some individuals also travel long distances during the warm season, going as far north as Rhode Island on the Atlantic coast or even to Texas along the Gulf of Mexico.

Manatees are federally listed as an endangered species that needs protection. Major threats to their survival are human activities: boat-related injuries and deaths, entanglement in fishing gear and discarded line, habitat loss or degradation, and in some countries, hunting.

Did you know? Manatee ancestors evolved from four-footed land mammals more than 60 million years ago, and manatees are distantly related to elephants and hyraxes; the latter are small mammals native to Asia and Africa.

Barred owls like this one were most strongly associated with patches of large hardwood and conifer trees in relatively flat areas along streams.

Invasive barred owls in the central Coast Range of western Oregon appear to be outcompeting the federally threatened northern spotted owl for critical resources such as space, habitat and food, according to a new study by the U.S. Geological Survey’s David Wiens. The study confirms that barred owls not only use similar forest types and prey species as spotted owls, but also that a high density of barred owls can reduce the amount of those resources available to spotted owls.

The northern spotted owl was designated as threatened under the Endangered Species Act in 1990. In recent years, however, the larger and more aggressive barred owl has expanded its range from eastern into western North America, where its geographic range now overlaps the entire range of the northern spotted owl.

Now, barred owls have become more common than spotted owls in the forests of western Oregon, according to Wiens, who received his Ph.D. at Oregon State University for this work. The three-year study was the result of a research partnership led by the USGS that included OSU, the U.S. Fish and Wildlife Service, National Park Service, Bureau of Land Management, U.S. Forest Service, Oregon Department of Forestry, and Boise State University.

Wiens’ study identified at least 82 pairs of barred owls but only 15 pairs of spotted owls. The barred owls had a 92 percent probability of surviving from one year to the next, compared to 81 percent for spotted owls. Furthermore, barred owls produced more than six times as many owlets as did the spotted owls over the study period.

Both species frequently used patches of old conifer forest or stands of hardwood trees along streams while hunting for food and roosting, and both species survived better when there were greater amounts of old conifer forest within their territories. But while barred owls are selecting older forest habitat, as shown in Weins’ study, they thrive in other habitats as well. In contrast, spotted owls are almost entirely dependent on older forests.

Weins said his study by itself doesn’t assess whether barred owls are making it difficult for the spotted owl to recover. He cautioned that he did not examine cause-and-effect relationships. Furthermore, the study area was limited and encompassed a highly fragmented landscape, conditions found in some but not all portions of the spotted owl’s range. However, the study does support the conclusion that barred owls are probably having a significant impact on spotted owls.

“Despite two decades of dedicated management efforts, northern spotted owl populations have continued to decline throughout much of their range,” said Eric Forsman, a U.S. Forest Service researcher who also participated in the study. “This study suggests that conservation of old forest habitat is still a critical need for spotted owls, so we will continue to work with our research and management partners to collect information and explore options for management.”

The full report, “Competitive Interactions and Resource Partitioning between Northern Spotted Owls and Barred Owls in Western Oregon,” is available as an Oregon State University doctoral dissertation.

Caretakers painstakingly feed, nurture, and teach the daily tasks of survival to whooping cranes all while hiding their true identity behind baggy costumes. The team members never use human voices, exercise and take the cranes for walks and swims, and use puppets to deliver food to the baby whooping cranes they care for — all so that they can be released to the wild.

Whooping crane chicks have definite personalities. Chick L10 was shy but blossomed into a rascal, and Chick L8 had an early tendency toward being a bit of a bully, but eventually learned to get along with his peers.

Whooping crane Chick L8 was hatched on June 4, 2010. When he was about a month old, he became a “meanie” toward other chicks and could not be walked with any other cranes. He had to live and exercise by himself for a long time and was the last bird to be socialized with the rest of his cohorts. But it turns out that Chick L8 was just a late bloomer, and he eventually learned to live peaceably with others. Chick L8 has a sister, who was also released in Louisiana.

Both of these gangly, adolescent whooping cranes were shot and killed in Louisiana on Monday, October 10, 2011, and though two alleged shooters have been identified, the world of whooping crane scientists, managers, caretakers, volunteers, and birders is in mourning — once again.

Tragically, these are the sixth and seventh shooting deaths of reintroduced endangered U.S. whooping cranes in 2011.

Here, at the USGS’s Patuxent Wildlife Research Center, in Laurel, Maryland, where we raised Chicks L8 and L10 until their release in Louisiana last winter, we find these killings personally and scientifically heartbreaking and ethically unacceptable.

These cranes — including each of those senselessly killed by people — represent an investment of hope for whooping cranes to wing their way back to a more certain future. And with only about 430 whooping cranes now in the wild, each bird counts.

At Patuxent, we have been raising whooping crane chicks for 45 years; the species had reached a low of about 16 adult birds by the late 1930s and was in grave danger of extinction, as they still are today. Whenever any of our chicks leave our USGS Maryland facilities for the wild, we bid them farewell with hope and, yes, a bit of parental worry for their future. We know some chicks won’t make it because survival is tenuous in the natural world.

Of the 10 cranes we raised and released last year in Louisiana, only 5 remain alive — one is presumed dead, another appears to have been eaten by a predator, and a third was euthanized because of a lung infection. But these shooting deaths are another thing entirely, and entirely preventable.

Each such death is a robbery of the investment made by the American public, and negates countless hours of careful work by scientists, aviculturists, volunteers, and others toward the conservation of this magnificent bird.

Whooping crane Chick L10 was hatched on June 9, 2010, from a breeding pair at the USGS Patuxent Wildlife Research Center. As a young chick, Chick L10 was timid about going into the back field for her exercise walks. But by the time she was released in Louisiana, Chick L10 had become confident and unafraid. She was even known for sneaking up on the costumed technicians and pecking at them.

Last year, when we sent these and eight other chicks to Louisiana, we celebrated with the State and others about the species return there after an absence of some 60 years. These shootings are, as the State of Louisiana noted, “a profound setback” for the reintroduction program. The death of two birds will not destroy the natural world, but the attitude that has led to the intentional killing of endangered species is a clear indication of the extent of education needed to develop a more generally accepted conservation ethic.

Ultimately, the understanding that human welfare is intimately and directly tied to conservation of intact natural ecosystems is crucial.

As for us, the USGS whooping crane team, we will continue raising chicks and working with our dedicated partners to restore this species because we believe that chick by chick, bird by bird, these cranes will and should have a chance to one day thrive in the wild again. It is wonderfully gratifying to be able to contribute to the survival of such a spectacular species and to recognize them as a symbol of how humans can conserve and even add to the ecological integrity of our environment.

John B. French, Jr., Ph.D., is the leader of the Whooping Crane Program at the USGS Patuxent Wildlife Research Center.

]]>http://www.usgs.gov/blogs/features/usgs_top_story/endangered-cranes-shot-and-killed/feed/0Caretakers feed, nurture, and teach the daily tasks of survival to whooping cranes all while hiding their true identity behind baggy costumes. The team members never use human voices, exercise and take them for walks and swims, and use puppets to deliver food to the baby whooping cranes they care for—all so that they can be released to the wild.Whooping Crane Chick L8L10Whooping crane Chick L10 was hatched on June 9, 2010, from a breeding pair at the USGS Patuxent Wildlife Research Center. As a young chick, Chick L10 was timid about going into the back field for her exercise walks. But by the time she was released in Louisiana, Chick L10 had become confident and unafraid. She was even known for sneaking up on the costumed technicians and pecking at them.Species at Riskhttp://www.usgs.gov/blogs/features/usgs_top_story/species-at-risk/
http://www.usgs.gov/blogs/features/usgs_top_story/species-at-risk/#commentsMon, 28 Mar 2011 12:05:36 +0000ocwebhttp://www.usgs.gov/blogs/features/?p=111944

An adult female polar bear and her two cubs travel across the sea ice of the Arctic Ocean north of the Alaska coast.

Polar Bears and Sea Ice: Polar bears were the first species listed as threatened because of observed and projected declines in sea-ice. Over the past 25 years, the summer sea ice melt period in the Arctic has lengthened, and sea ice cover has declined dramatically. Since 1985, scientists at the USGS Alaska Science Center have conducted research on polar bears to inform policy makers regarding conservation of the species and its habitat. Ongoing studies are designed to document population responses of polar bears to changing ice conditions and refine models used to project the future status of polar bears worldwide. These studies will provide managers with information needed to develop strategies to assure long-term polar bear survival in a changing ice environment.

USGS Sea Otter Studies Clue in on Coastal Health: Sea otters are a favorite at zoos and aquariums but three of the nine wild sea otter populations in the U.S. are federally listed as threatened. In California, USGS biologists lead an annual population census to assess the local populations’ recovery, working closely with state agencies and the Monterey Bay Aquarium. USGS biologists are also teaming up with government, aquarium, and university researchers to conduct the Pacific Nearshore Project, which assesses the health of coastal waters and resources in Alaska, British Columbia, Washington, and California. Scientists will investigate sea otter populations in these waters for critical clues to the health of these economically and ecologically important habitats.

history, population dynamics, and ecological requirements of the West Indian manatee. Federally listed as endangered, the manatee is a large, gentle, plant-eating, and slow-moving marine mammal. Entirely aquatic, their range is limited by temperature. Manatees cannot survive for extended periods in water colder than about 63°F. USGS biologists work cooperatively with federal and state researchers and managers on research identified as essential for the recovery of the species.

The Whooping Crane: Back from Extinction: Large and majestic, the whooping crane was once on the brink of extinction. America’s tallest bird stands five feet tall with a wingspan of about eight feet, and is federally listed as endangered. All the birds alive in North America, currently about 250 birds, are descendants from a flock of only 16 individual birds. USGS is engaged in a whooping crane captive breeding program and conducts research on whooper propagation, monitoring wild populations, survival of released birds, and veterinary care.

After breeding numbers of spectacled eiders, a large sea duck, declined by 96 percent at a primary breeding area in Alaska, the species was listed as threatened. Potential risks to eiders include being subjected to increased exposure during storms in winter, changes in foods because of declining ice, and warming temperatures in the Bering Sea. Increased vessel traffic in new ice-free shipping lanes may also impact eiders. To evaluate these potential threats, USGS is using satellite telemetry to track eiders when these colorful birds are in the Bering, Chukchi, and Beaufort seas. Scientists have already located previously unknown wintering areas of these birds, and studies are continuing to document changes indistribution and abundance in the rapidly changing Arctic.

Jeepers! Those Endangered Honeycreepers: Climate change and disease threaten many species of Hawaiian honeycreepers, unusual birds that live in high-elevation rain forests on the islands of Kauai, Maui, and Hawaii, which are cool enough to limit transmission of the introduced disease, avian malaria. USGS scientists have documented recent dramatic increases in avian malaria on the Alakai plateau on Kauai that could affect recovery of two endangered honeycreepers, the ‘Akikiki (Kauai creeper) and `Akeke`e (Kauai akepa), and one endangered thrush, the puaiohi (small Kauai thrush). They are continuing to work on projects to determine how some more common native forest birds may be adapting to this disease and whether they hold important keys for long-term conservation of more threatened species.

In addition, USGS scientists have studied the critically endangered palila for 25 years; this species feeds on the seeds of the māmane, a native tree that is nutritious but toxic to many other vertebrate species. The palila population has declined steadily during the past 8 years, putting the remaining 1,300 birds at very high risk of extinction. USGS biologists have provided much-needed information on palila life history and on developing restoration techniques, including returning palila to portions of their former range. Some of those birds established a breeding colony at the new site, proving the potential value of translocation for reestablishing populations. Much of the recent decline is due to drought, but long-term browsing by introduced sheep has also reduced the ability of the palila’s subalpine woodland habitat to support them. New research will help managers evaluate how vegetation responds to periodic sheep removals. For more info on climate change and honeycreepers.

What a Breeding Western Yellow-Billed Cuckoo Wants: The western yellow-billed

A Western Yellow-Billed Cuckoo

cuckoo is a shy, neotropical migrant bird once common throughout the American West; it is currently a candidate for protection under the Endangered Species Act. After spending the winter in South America, western cuckoos arrive in the Western United States beginning in June to breed along rivers and streams. The western cuckoo, however, has disappeared from the Pacific Northwest and Canada, leaving breeding to occur in isolated areas along rivers in Arizona, California, and New Mexico. Scientists with the USGS and Northern Arizona University studied this bird along the lower Colorado River in Arizona to understand its habitat needs. This research revealed that western cuckoos prefer habitat dominated by large continuous areas of streamside habitat dominated by native trees.

Mussels on the Edge: Native freshwater mussels are among the most fascinating, widespread, and endangered animals in fresh waters. They play important ecological roles in our lakes and rivers and their shells are used to produce cultured pearls. Mussels are threatened by changes in flow patterns within rivers caused by dams, dikes, and levees; by sediment increases in rivers and streams; and by invasive species, such as zebra mussels and Asian carps, that compete with mussels for food. Rising water temperatures and drought that may result from climate change have the potential to adversely affect the health and valuable services of mussel populations even more. Research conducted by USGS scientists and partners are showing how elevated temperatures may affect the survival, growth, reproduction, and physiology of native mussels.

Mojave Desert Tortoise found in Piute Valley in Clark County, Nevada, in 2005

USGS Delves Into Desert Tortoise Dangers:

The Mojave desert tortoise is federally listed as threatened — facing dangers such as habitat fragmentation, climate warming, as well as invasive grasses, which overrun native vegetation and increase risk of deadly wildfires. USGS biologists are using genetic studies to uncover whether these long-lived reptiles are experiencing isolation and inbreeding due to habitat loss, and conducting comprehensive habitat mapping to determine whether sufficient habitat corridors exist for tortoise populations to naturally to move across their native desert landscape — where the burrows they dig help jumpstart local ecosystems.

USGS Research Gives Endangered Frogs a Second Hop at Survival: As part of the USGS Amphibian Research and Monitoring Initiative (ARMI; http://armi.usgs.gov/), USGS biologists are leading the monitoring and reintroduction effort of the Southern California mountain yellow-legged frog — federally listed as endangered with only 200 wild adults remaining in the mountains surrounding Los Angeles County. Working with biologists at the San Diego Zoo, USGS biologists help reintroduce zoo-bred tadpoles and eggs to wild streams, and study their survival and how wildfires and invasive species affect these frogs.

Elevated Extinction Risk for Mountain Salamander: The Shenandoah salamander is a

Shenandoah Salamander

small, terrestrial woodland salamander found only within the Shenandoah National Park. Like other high-elevation species, this salamander is severely threatened by climate change, which is expected to result in dramatic temperature and moisture changes in the Appalachians. Because many high-elevation salamander species are specifically adapted to the unusual conditions typical of these sites, they may not be able to survive the changing conditions in the future without management. Compounding their risk is that many of these high-elevation species have extraordinarily small ranges, including the endangered Shenandoah salamander. USGS ARMI (Amphibian Research and Monitoring Initiative; http://armi.usgs.gov/) scientists are combining detailed habitat models (these show where the species occurs) with experimental tests of the fate of the species under future climate conditions to forecast the extinction risk for this species and to provide information to the National Park Service on the best way to help lessen this extinction risk.

A Devilish Situation for the Devils Hole Pupfish: Contained deep within a limestone cavern in the Mojave Desert, Devils Hole is a constant temperature (93 degrees), 10 by 50 foot pool of water. Devils Hole pupfish live only in Devils Hole, dependent on a tiny spawning shelf less than 13 feet long and 7 feet wide. There, these tiny colorful fish – the males a sparkling blue, the females a more subdued grey-blue or silvery-blue – have made their home for thousands of years. Devils Hole pupfish populations remained about 400-500 individuals until the late 1960s when the water level in the pool dropped in response to pumping of nearby irrigation wells. Pupfish numbers declined precipitously, and though water in Devils Hole is now maintained at a minimum level, the pupfish are still greatly imperiled. With intensive management efforts, pupfish numbers are increasing from a critical low of just 38 individuals in 2006 to about 118 in 2010. USGS scientists and their partners are using video to help them assess relationships between environmental conditions and spawning in the pupfish to help managers better understand the habitat and spawning requirements and ultimately help in captive propagation.

A Face Only a Mother Could Love: The endangered humpback chub is a freshwater fish found only in the Colorado River Basin. Like other native Colorado River fish species, the humpback chub has an unusual body shape, presumably an adaptation to life in a large, active river. The USGS has developed a mark-recapture model to estimate adult population trends and the number of juvenile fish surviving to adulthood for the Grand Canyon population. The most recent USGS analysis indicates that the number of Grand Canyon adult humpback chub—fish 4 years old or older and capable of reproducing—increased by about 50 percent between 2001 and 2008. Scientists estimate that there are about 7,650 adult fish in the Grand Canyon population.

The Merrimack River draining northeast Massachusetts and New Hampshire is home to two sturgeon species: the shortnose sturgeon (federally endangered) and the Atlantic sturgeon (under consideration for federal listing).

Coastal Migration of Merrimack River Sturgeons:

The Merrimack River draining northeast Massachusetts and New Hampshire is home to two sturgeon species: the shortnose sturgeon (federally endangered) and the Atlantic sturgeon (under consideration for federal listing). Atlantic sturgeon make extensive coastal migrations, but those captured within the Gulf of Maine appear to remain within the region. Developing interests in coastal hydro-kinetic power turbines (these harness the power from moving water), particularly in Canadian waters, may prove to be a significant threat to coastal-wandering sturgeon and a more detailed understanding of their movements may assist hydro-kinetic development. Until recently, shortnose sturgeon were believed to spend much of their lives within their natal river system, particularly populations in the northeast and Gulf of Maine. A recent collaboration of the USGS with university and state partners identified a previously unobserved coastal spawning migration of pre-spawning female shortnose sturgeon.

]]>http://www.usgs.gov/blogs/features/usgs_top_story/species-at-risk/feed/0polarbear_with_coysAn adult female polar bear and her two cubs travel across the sea ice of the Arctic Ocean north of the Alaska coast.manatee_portraitA Manatee in Floridabird_male_transmitterA Male Spectacled Eider in AlaskacuckooA Western Yellow-Billed Cuckoodesert_tortoisMojave Desert Tortoise found in Piute Valley in Clark County, Nevada, in 2005salamanderShenandoah SalamandersturgeonThe Merrimack River draining northeast Massachusetts and New Hampshire is home to two sturgeon species: the shortnose sturgeon (federally endangered) and the Atlantic sturgeon (under consideration for federal listing).